JANUARY 3, 1907 | 
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The first part of the second volume of the expedition 
reports is devoted to a full description of the geo- 
graphy and geology of the Gaussberg. It includes 
three memoirs. A detailed account of the geography 
of the mountain is given by Prof. von Drygalski, in 
which he describes its form, position, and glaciation. 
The most interesting part of von Drygalski’s report 
deals with the glaciation and the forms of the moun- 
tain. The inland ice from Antarctica abuts against 
the southern slope of the Gaussberg, although as a 
rule its junction with the inland ice is hidden by ice 
of local origin. The mountain is 370 metres in 
height, and it was at one period completely over- 
ridden by ice from the south; and the admirable 
photographs which accompany Dr. Philippi’s report 
illustrate the subdued glaciated contours of the whole 
mountain. Some moraines occur on it, and indicate 
transport from south to north. 
The valleys upon the flanks of the Gaussberg are 
not due to erosion, but are depressions between the 
lava streams or along lines of rapid weathering. In 
his description of the mountain, Prof. von Drygalsli 
obviously writes with great restraint to prevent in- 
fringing on the geological report 
contributed by Dr. Philippi, whose 
memoir is accompanied by a series 
of excellent photographs of the 
mountain, its moraines, and_ its 
lavas. The whole mountain is com- 
posed of volcanic rocks, which are 
described in full petrographic detail, 
accompanied by analyses and illus- 
trations, by Dr. R. Reinisch, of 
Leipzig. The rocks are leucite- 
basalts and leucite-basalt tuffs, rich 
in glass. The only other indigenous 
rocks occur as ineclisions in the 
lava; they are nodules of olivine and 
fragments of pyroxene-gneiss and 
pyroxene-granite, which appear to 
indicate that a platform of plutonic 
rocks occurs at a comparatively 
slight depth below the basalts. 
The age of the mountain is 
doubtful, but appears to be late 
Cainozoic. Dr. Philippi suggests 
that the eruptions may have begun 
in the Pliocene, and, in his opinion, 
they were either late Pliocene or 
Pleistocene. The local glaciers 
Dr. Philippi describes as  com- 
paratively unimportant in their development. Erratic 
blocks from the inland ice that once covered the 
whole mountain are scattered to its summit. The 
erratics include boulders of granites, gneiss, amphi- 
bolites and other crystalline — schists, with some 
quartzites, sandstones, and conglomerates. They in- 
dicate the continental structure of the land to the 
south. The section of Dr. Philippi’s report which is 
probably of most general interest discusses to which of 
the two coastal types this land belongs. According 
to Reiter’s well-known suggestion, Wilkes’ Land is 
of the Atlantic type, while Victoria Land, as the con- 
tinuation of the New Zealand line, is of the Pacific 
type. The evidence available from Cape Adare and 
Kaiser Wilhelm Land suggests that all the inter- 
vening coast is of the Atlantic type. According to 
Dr. Philippi, Victoria Land is the same. His con- 
clusion rests on two considerations. Firstly, Victoria 
Land is a plateau land, and when Suess originally 
distinguished the Atlantic and Pacific coast-types he 
regarded coastal plateaus as confined to the Atlantic 
type. The coast of northern Queensland is, how- 
ever, in part a plateau edge, but it may be retained 
in the Pacific type, as its characters have probably 
NO. 1940, VOL. 75 | 
been determined by a succession of step faults parallel 
to the coast, a structure which Prof. Suess describes 
as characteristic of the Pacific type. 
No doubt these inner step-faulted coasts of the off- 
lying seas of the Pacific are younger than the outer 
folded coast of the main ocean, and it may be con- 
venient to separate them as secondary Pacific coasts. 
If so, then Victoria Land may be described as having 
a secondary Pacific coast, like the southern end of 
New Zealand and the eastern coasts of Australia; 
and the outer folded Pacific coast may then have 
passed from the middle of the South Island of New 
Zealand eastward towards Graham’s Land along a 
line which is still unknown, and has perhaps been 
completely destroyed. 
Unless the Pacific coast type is to be so re-defined 
as to assign an Atlantic structure to much of the 
Pacific coast, no adequate tectonic reason has been 
yet advanced for the removal of Victoria Land from 
the Pacific group. The second argument for this step 
is petrographic. _Becke and Prior have both sug- 
gested that the Pacific and Atlantic types of coasts 
are characterised, not only by different tectonic struc- 
Fic. 1.—Edge of the Inland-Ice and Moraines at the north-western corner of the Gaussberg. 
tures, but by different groups of volcanic rocks. The 
volcanic rocks erupted along the Pacific folds are 
richer in silica, alumina, soda, and magnesia, and 
the volcanic rocks discharged from the fractures along 
the Atlantic shores are richer in potash, lime, and 
iron oxides. The characteristic volcanic rocks of the 
Pacific are rhyolites, dacites, andesites, and acid 
basalts. Those characteristic of the Atlantic are 
trachytes, phonolites, tephrites, and basic basalts. 
The affinities of the volcanic rocks of the southern 
end of New Zealand and of Cape Adare are with 
the Atlantic group. As a rule, the distribution of 
Becke and Prior’s petrographic types coincides to a 
remarkable extent with Suess’s two tectonic divisions 
of the coasts of the world; but the petrographic and 
tectonic features do not appear to coincide universally, 
and it is doubtful whether the former is as suitable a 
taxonomic character as the other. 
The Gaussberg area, situated as it is at the western 
end of Wilkes Land, is of such special interest that 
it is unfortunate that circumstances prevented the 
German explorers from reaching a wider extent of 
land, as these memoirs show the high quality and 
thoroughness of their work. Ile AWS (ic 
